Arc lamp



1937- A. RUTTENAUER ET AL 2,069,080

ARC LAMP .Filed Jan. 26, 1932 [Wpmraas ALFRED RUTTENAUE'R.

"UT'T'U Fara-'22? 4K Tarn-L Ar '2" mummy Patented Jan. 26, 1937 UNITED STATES ARC LAMP Alfred Riittenauer, Berlin-Gharlottenburg, and

Otto Fritze, Berlin, Germany, assignors to General Electric Company, a corporation of New York Application January 26, 1932, Serial No. 589,004 In Germany February 23, 1931 3 Claims. (01. 1761) Our invention relates to are lamps of the type which comprises highly refractory electrodes having a filament mounted in multiple therewith sealed in a light transmitting enclosure contain- 5 ing an inert gas or vapor. More particularly our invention relates to means for supporting said.

filament. The filament m such a lamp is provided for the purpose of facilitating the formation of an are between the electrodes by ionizing the gas therebetween due to the emission of electrons, from said filament. With the present methods of mounting the filament, the arc first allow the passage of current therethrough at the comparatively high starting voltage but will con- 25 siderably impede the flow of current when the voltage drops and the arc appears, so that said arc will appear initially across .the electrodes. Other features and advantages of our invention will appear from the following detailed descrip- 30 tion of species thereof.

In the drawing, Fig. 1' is anelevation of a lamp comprising our invention; and Figs. 2 and 3 are detailed views in perspective of modifications of the filament connections.

5 Referrifig to Fig. 1, the lamp comprises a bulb l and base if. i For the purpose of transmitting ultra-violet radiations, said bulb Ill, containing argon, nitrogen, or other inert gases or vapors, may be made of quartz glassor of a borosilicate glass free from lead and iron. The lamp also comprises a stem tube I2, an exhaust tube I3, outer lead wires I4, conductors l connected thereto and sealed into a stem press l6, and inner lead wires I! connected to said conductors I5. 45 Support wires l8 mounted on inner lead wires I! carry electrodes l9 of a highly refractory metal such as tungsten. The support wires-are provided with loops 20 which support loosely the ends of a filament 2| .hanging therefrom. Said 50 filament 2| is further supported by a loop 22 at the end of a wire 23, the other end of which is held by aninsulating disk 24 which is in turn held up by support wires 25 mounted on the inner lead ll. In order to obtain a substantial 55 amount or ultra-violet radiation it is preferred to include a small quantity of mercury 26 so that mercury vapor will be formed and its radiation will be added to the light.

Referring to Fig. 2, a filament 2'lcomprises a single loop passing through the loops 20 of the support wires l8 and hanging loosely therefrom. Said filament 21 is further supported, to hold it open in .the form of a loop in difierent positions of the lamp, by loops 28 at the ends of wires 29 which are in turn supported by a disk 30 similar to disk 24 in Fig. l.

Referring to Fig. 3, support wires 3| mounted on inner lead-in wires H are flattened at portions 32 in which holes are provided for the reception of pins 33 comprising heads 34 which seat loosely on the portions 32. A filament 35 is clamped or welded at each end to the ends of pins 33 and is additionally supported in a loop 36 at the end of a. wire 31 similar to the wire 23 in Fig. 1.

What we claim as new and desire to secure by Letters Patent of the United States, is:

1. In an electric-lamp, the combination of a pair of separated electrodes, a filament in multiple with the gap between said electrodes and means for supporting said filament and having a loose connection therewith comprising lead wires having holes therethrough and headed pins passing through said holes and united to said filament.

2. In an electric discharge lamp, the. combination of a bulb,.a pair of inner leads in said bulb for carrying current, an electrode secured to each of said leads, and a filament connected in multiple with the gap between said electrodes and supported a by said inner leads, the connection betweenfilament and leads being of sufliciently high resistance to allow the passage of current through said filament at the comparatively high starting voltage of the lamp but considerably impeding the flow of current when the arc appears and the voltage drops so that the said arc appears initially across the electrodes.

3. In an electric discharge lamp, the combina- 40 tion of a bulb, a pair of inner leads in said bulb for carrying current, an electrode secured to each of said leads, and a filament connected in multiple with the gap between said electrodes and supported by said inner leads and having a loose connection therewith, the area of contact between said-filament and leads being comparatively small so as to produce a high resistance, the

that t e said arc appears initially across the electrodes.

ALFRED RU'I'I'ENAUER. o'rro FRITZE. 

